Clinical experience with antiinflammatory agents in patients with sepsis has been disappointing to date. We have found that severity of infection has an important influence on many of these agents. Developing new agents which are impacted minimally by this factor, will increase the usefulness of this therapeutic approach. We are presently performing a series of studies investigating the influence of severity of infection on a recently developed tyrosine kinase inhibitor. In early studies with this agent, severity of inflammation related to endotoxin challenge did little to influence the beneficial effects of this agent.